Subject: RE: Raith problem --> NO PROBLEM !!
From: Luigi Scaccabarozzi <>
Date: Tue, 13 Jul 2004 23:47:00 -0700 (PDT)

Thanks to Joe for the explanations, but if I tried to do things exactly
like in past, can you tell me why now it is not working? I mean, what
other parameters on LEO could have possibly changed so that now the zoom
exceeds the limit?

And, if I simply decrease the MAG, what's going to happen to resolution
and other parameters?

One last question: I thought that the values of zoom-x and zoom-y depend
on the WD, as well on other parameters. I tried to change WD (from 5 to
10), keeping all other parameters constants and the numbers don't change.
Is this normal?

I also noticed doing the align WF that in the first two scan my mark is
"reasonably" shifted from the center, whereas in the third scan is
extremely shifted (which makes zoom-y exceed the limit). What do you think
about it?
Thanks for your time

On Wed, 14 Jul 2004, Joseph Klingfus wrote:

> Greetings users.
> There is nothing wrong with the pattern generator.
> A key observation is that the Magnification Display of the LEO was not set
> to Polaroid.  This is not the first time I have heard of this happening.  It
> is set correctly when a user account is first added, but then somehow
> becomes set to current output device.  So far we are not able to repeat how
> it occurs.  Please check this setting the next time you log onto the SEM.
> Important notice concerning "zoom exceeds limits"....
> If you have never experienced this message before, then you have probably
> always used a default WF size and have never tried to setup your own WF
> size.  Within the Microscope Control window the relationship between
> microscope MAG and WF size is only a very "course" field setting.  The "fine
> tuning" is done with the AlignWF procedure and the resultant field scale
> parameters (zoom, shift, rot.) are displayed/stored in the Align WF window.
> There are max limits set on the DACs to keep their output response linear.
> If "zoom exceeds limits" then just decrease the MAG for the given WF size,
> this will decrease the needed zoom value.  This message is in no way an
> indication that there is a deficiency or problem with the tool.
> Joe.
> -----Original Message-----
> From: Luigi Scaccabarozzi []
> Sent: Tuesday, July 13, 2004 11:15 PM
> To: raith@snf.Stanford.EDU
> Cc:; Kahl, Michael; jwc@snf.Stanford.EDU
> Subject: Raith problem
> Hi all,
> ryan and I have found problems today in WF alignment. The error is
> "Zoom(Y) exceeds limit". I tried resetting and shutting down computers and
> Elphy, but no way. I tried WF align at WD 4.6 to 10 mm and the numbers of WF
> correction are the same. It looks like that the Elphy is stuck on those
> numbers (zoom X=1.49, zoom Y=1.52). I talked to James, and he says to try
> again tomorrow morning (Ryan is next user) after leaving the Elphy OFF for
> ~20 min (which I just did). If it still does not work, tomorrow morning we
> can call him and/or Raith. If people from Raith have any idea or suggestion
> are welcome otherwise James plan is to have another Elphy shipped here
> tomorrow.
> One more thing. I noticed that the option on LEO Tools-> Preferences-> SEM
> condition-> device was set to current device instead of POlaroid 545. No
> idea how that could have been switched but check your account. If polaroid
> is not selected, Align writefiled will definitely not work. If you have the
> wrong option, select polaroid, click apply and reboot both systems.
> Any help welcome
> Thanks
> Gigi